lower shrouds

[jhenson]

I understand that early Tritons had only a single lower shroud. My boat had a set of forward lowers added a later date. I can see that the chain plate is of a different manufacture than the others.

The problem lies in how they are secured below decks. The chainplates are attached to a piece of angle iron (about 1X1X12) with a single bolt. The angle iron is not attached to anything, so the chainplates can move up an down with a sawing action as the rig flexes in both directions. I don't think any amount of bedding compound would survive this movement for long. Hence, there is a major leak through them.

I would be interested in how later boats are secured.

[bcooke]

I think I read somewhere that the forward shrouds really are not needed and they were added just to make owners feel better. I don't know if that is true but having the extra set does make me feel better.

My late model Triton (#680) has the forward shroud attached to a chainplate identical to the aft shroud and it is bolted to the aft side of the forward bulkhead with three bolts.

the angle iron is not attached to anything,

Maybe I just can't picture it but are you saying the angle iron just rests under the deck and prevents the chainplate from being pulled up too far? I had heard that early owners often added shrouds of their own design but that is amazing peice of design work. Got any pictures? I spent some time on my chainplates this last summer and could probably locate a pretty clear picture if you want and Tim can host.

-Britton

[dasein668]

Strictly speaking, the forward lowers are not needed; evidenced by the fact that 5 or 6 hundred Triton rigs have stood up for 40+ years with out them.

However, that is not to say that they do not help stabilize the rig. They definitely do, especially helping to minimize pumping of the mast.

Your installation sounds suspect and much like PO upgrade as indicated by Britton.

That said, however, you probably don't need anything too overly engineered for those lowers either. I think that a heavy duty padeye secured with a decent backer block would be plenty for the purpose.

[JetStream]

The following passages are quoted from a book by Dorwin W Teague about the early Tritons. The shroud you speak about may be part of that history. It is nice to know for all Triton owners anyway:


One of our design accounts was a new boat for the Pearson Corporation that came about as a result of my purchase of the Triton. After our Bermuda trip, which received some publicity, we began to race Ole' in the Eastern Long Island Sound series and a few distance races. I became annoyed at the extreme weather helm and finally took the drastic step of cutting the main boom down from fourteen to twelve feet and had the mainsail re-cut accordingly We began to beat other Tritons consistently Our friend Tom Harrison and some of our other competitors followed our example. Finally the Pearson Corporation made this a production modification although, as I remember, a bit more conservatively by cutting back the fool of the sail by only 1-1/2 feet. A more serious inherent fault began to show up as several Tritons had mast failures during hard blows. Ole' was leading a race off Larchmont by a good margin, when our mast suddenly went over the side. By this time the insurance companies were getting a bit fretful and the Pearsons (Everett and Clint, who are cousins) decided something had to be done so they hired me as a consultant to try to find out what was going on.

I inspected five or six failed masts in the Long Island Sound and New England areas and discovered all the failures were identical. The mast, stepped on deck in the Tritons, had all failed by bending aft at the spreader line. This brought to mind the knock-down on our Bermuda trip, after which both spreaders were angled forward. I couldn't figure this out for a while but finally the answer came to me. Carl Alberg had designed the Triton with a single lower shroud, a legitimate system if done right. But there was a bulkhead in the Triton a foot aft of the mast line; the Pearsons assumed the chainplates for the lower shrouds would be much more secure if attached to this bulkhead rather in line with the mast, as called for in Alberg's design. What this did, however, was to produce a strong after-force component on the mast right at the spreaders, a weak point anyway because of the hole for attaching the spreaders. We were lucky that our mast hadn't failed on the way to Bermuda. We designed a "recall" kit for the existing Tritons, while the Pearsons corrected the problem in later ones.

The book is: Industrial Designer, The Artist as Engineer
W.Dorwin Teague.

I was more interested in it for one of his other boats (Souffle', a 1961 Tripp Javelin, but he sailed his Triton to Bermuda and it is an interesting story.

[dasein668]

We designed a "recall" kit for the existing Tritons, while the Pearsons corrected the problem in later ones.

Must have been the MUCH later ones, since 668 of 712 doesn't have the forwards...

Interesting story. I knew that they had a retrofit kit, though I didn't know it was due to lost rigs.

[bcooke]

#668 doesn't have the forward shroud?... Interesting. I would have thought that mine (only twelve boats later in the 'assembly' line) came with double shrouds from the factory because all the chainplates are of identical manufacture and installation. It could be that they were all changed at a later date but that would be unusual.

The forwards on my boat were installed a little suspect as on both sides on of the boltholes on each missed the bulkhead (bulkhead has about a one inch gap from the hull) and wasn't holding against anything. I assumed it was a Pearson slap-together job but maybe I have been judging them too harsh for other peoples lack of common sense.

Now that I think of it, I posted earlier that the installation was identical. I am thinking now the forward chainplates only had two bolts holding them in instead of the three on the aft shrouds. I will take another look.

-Britton

[Tim]

Here's yet another situation where one published account that tries to generalize the production changes of the Triton is still inaccurate. There are so many differences from boat to boat that it's impossible to generalize or point to a specific feature as evident only after hull# so-and so.

I had read earlier that the supposed slew of lost rigs were actually some of the earlier tapered spars, which were changed sometime in the low 100s (again, no one seems to be able to point to exactly when). The tapered spars on the early boats have narrower spreaders that also tend to droop and don't have the proper upward angle, which I also feel would contribute to failures. The untapered section that most of us have is significantly longer in section (longitudinally) than the old tapered spars, which would also serve to help stiffen it in that direction.

Spartan Marine makes a nice deck-mounted chainplate fitting that would be appropriate for aftermarket installation of forward lowers, along with a beefy backing plate below decks. The forward lower only need to reduce or eliminate the tendency of the mast to pump in a backwards direction, towards the pull of the aft lowers, and therefore do not need to be extremely highly tensioned. A good deck fitting with proper installation and backing would be more than sufficient.

When I get around to installing forward lowers on Glissando, these Spartan fittings are the ones I will use.

[Tim]

Oh, and that "recall" kit, by all accounts and by some installations I have seen (where I was told it was the kit) was a complete joke and worthless in its performance--some lousy deck fitting and so forth.

[jhenson]

Here is a picture of the situation:



The picture isn't very good because of the amount of dust in the v-berth area right now. I am grinding off old paint. The image is of the port side standing just ahead of the v-berth aft bulkhead.

I like the thought of a padeye. Simple and inexpensive!

Thanks,

Joe Henson

P. S. I have a virtually new tapered mast, so I quess that it was attempt to duplicate the original (which was also tapered). Hull number 114.

[Tim]

Is that thing bolted through the hull, or does it literally act like one of those little chain stoppers that you find inside your deck fill plate to keep the cap from disappearing?

Whatever the case, that's pretty worthless! A nice padeye with broad backing plate would be much better and would work fine for the way most of us sail our boats. Remember that the forward lowers do not need to be super-tight to be effective. If you want to tweak your rigging and bend the spars (race-type tuning), then a more substantial chainplate with fiberglassed knee would be the recommended course.

[Tim]

Here are pictures of Britton's setup.

Port Chainplates


Starboard Chainplates


Scene at the Boatyard

[bcooke]

Thanks for hosting the pictures Tim, I would have to agree that that is a pretty amazing method of tying a shroud to the hull.

Now Joe, where exactly do your shrouds attach too? Are your forwards in the V-berth section? My forwards are on the forward bulkhead, as you can see from my pictures, and the aft shrouds fasten to knees about 16 inches aft of the bulkhead. Just curious, what is your hull number?

I threw in the picture of the boatyard as it looked this morning when I went out to take those photos. This is why I don't get much done in the winter. The tide is up and currently flooding the yard and there are "icebergs" floating nearby. So instead I putter around repairing tiller handles, scraping off paint from small parts, and generally thinking about what to do instead of just doing it. Now if I had a heated, dry boatshed...

Actually I wouldn't have any excuses so maybe I will leave it well enough alone :-)

-Britton

[Tim]

Now if I had a heated, dry boatshed...

Actually I wouldn't have any excuses so maybe I will leave it well enough alone :-)

I promise you that the guilt one feels when thinking about a warm, empty boatbarn with no work being performed inside is quite strong! There's little room for excuses, for sure.

[jhenson]

Those pictures of Britton are what I kinda thougt the setup would look like on a well done job. I was entertaining glassing over solid oak like the one in the head compartment. I think that my attachment point is exactly in the same location. Again, a padeye with these shrouds tensioned less than the others makes good sense and less work for a guy who is already overwhelmed with the magnitude of the task at hand.

Here in Northern Virginia, we have a pretty mild winter, so I can get a lot of stuff done inside the boat especially. We will pay for it though in about 5 months. I have really resisted the idea of building a temporary boat shed for that reason.

Thanks,

Joe

Hull #114

[jhenson]

I just spoke in error. I didn't read the post carefully enough. Mine attach in the V-berth just about 8" ahead of the V-berth bulkhead.

Joe

[bcooke]

Interesting...

Don't worry about the project. Once you get started you will realize it is not that bad. Installing the new knees was the biggest job I had done to date and I am pretty happy with the results. Next time I could do better and sometimes I wonder what I could have done with vacuum bagging...

I would say the padeye is the easiest way to go but if you wanted to move the shrouds aft to the forward bulkhead then you are just looking at cutting a new slot in the deck, fabricating or buying new chainplates, and drilling the bolt holes through the bulkhead. Either way wouldn't be a problem but using padeyes in the current placement means you know the shroud length won't need to change and gaining access is a non-issue.

Have fun!


-Britton

Oh, and Tim, if you ever feel guilty about not working, check out a cool website www.triton381.com. Any guy that does that much work can afford to lean back and rest on his laurels now and again.

[Tim]

Britton,

Your forward lowers attach to the forward bulkhead? That's where my uppers attach. The aft lowers have their own glass-covered oak knees about 8-12" aft of the forward bulkhead, and I have no forward lowers.

This seems to be yet another one of those variances between boats...unless there's some confusion here. I think I remember that the shroud attachment points on #100 were different than those on #381, but I don't remember the details offhand. I'll dig through some photos later and see what I can find.

[bcooke]

Hmmm.... well.... I guess this is where it will become obvious that I don't know what I am talking about...

You see... I haven't actually ever stood the mast up so I am not intimately familiar with the rigging. I have two chainplates per side which I have rebuilt (the bulkhead fitting had one bolt that missed the bulkhead and the other two bolts were surrounded by rotten plywood; the glassed in knees had mushy core from years of water intrusion) and that would mean.... that I don't have forward lowers by the sound of it. I forgot about the aft lowers. I hate it when my ignorance gets broadcast to the world though I suppose everyone on this forum already knew my mental status.

Sorry for the confusion. Just go ahead with whatever seems right :-)

-Britton

[bcooke]

In a feeble and inept means to redeam myself, I borrowed a picture from James Baldwin's website. I don't think he will mind. It shows his forward chainplate installatoin. I will forward the picture for Tim to post.

-Britton

[bcooke]

Wait a minute.. it is already posted so I just need to paste in this link here...


Hmmm... that should do it.

[jhenson]

Thanks for the picture. That looks very stoutly built!

Joe Henson